Пример #1
0
static int set_termios(struct tty_struct * tty, struct termios * termios,
			int channel)
{
	int i;
	unsigned short old_cflag = tty->termios->c_cflag;

	/* If we try to set the state of terminal and we're not in the
	   foreground, send a SIGTTOU.  If the signal is blocked or
	   ignored, go ahead and perform the operation.  POSIX 7.2) */
	if ((current->tty == channel) &&
	     (tty->pgrp != current->pgrp)) {
		if (is_orphaned_pgrp(current->pgrp))
			return -EIO;
		if (!is_ignored(SIGTTOU)) {
			(void) kill_pg(current->pgrp,SIGTTOU,1);
			return -ERESTARTSYS;
		}
	}
	for (i=0 ; i< (sizeof (*termios)) ; i++)
		((char *)tty->termios)[i]=get_fs_byte(i+(char *)termios);
	if (IS_A_SERIAL(channel) && tty->termios->c_cflag != old_cflag)
		change_speed(channel-64);

	/* puting mpty's into echo mode is very bad, and I think under
	   some situations can cause the kernel to do nothing but
	   copy characters back and forth. -RAB */
	if (IS_A_PTY_MASTER(channel)) tty->termios->c_lflag &= ~ECHO;

	return 0;
}
Пример #2
0
static int check_change(struct tty_struct * tty, int channel)
{
	/* If we try to set the state of terminal and we're not in the
	   foreground, send a SIGTTOU.  If the signal is blocked or
	   ignored, go ahead and perform the operation.  POSIX 7.2) */
	if (current->tty != channel)
		return 0;
	if (tty->pgrp <= 0 || tty->pgrp == current->pgrp)
		return 0;
	if (is_orphaned_pgrp(current->pgrp))
		return -EIO;
	if (is_ignored(SIGTTOU))
		return 0;
	(void) kill_pg(current->pgrp,SIGTTOU,1);
	return -ERESTARTSYS;
}
Пример #3
0
/*
 * This only works as the 386 is low-byte-first
 */
static int set_termio(struct tty_struct * tty, struct termio * termio,
			int channel)
{
	int i;
	struct termio tmp_termio;
	unsigned short old_cflag = tty->termios->c_cflag;

	if ((current->tty == channel) &&
	    (tty->pgrp > 0) &&
	    (tty->pgrp != current->pgrp)) {
		if (is_orphaned_pgrp(current->pgrp))
			return -EIO;
		if (!is_ignored(SIGTTOU)) {
			(void) kill_pg(current->pgrp,SIGTTOU,1);
			return -ERESTARTSYS;
		}
	}
	for (i=0 ; i< (sizeof (*termio)) ; i++)
		((char *)&tmp_termio)[i]=get_fs_byte(i+(char *)termio);

	/* take care of the packet stuff. */
	if ((tmp_termio.c_iflag & IXON) &&
	    ~(tty->termios->c_iflag & IXON))
	  {
	     tty->status_changed = 1;
	     tty->ctrl_status |= TIOCPKT_DOSTOP;
	  }

	if (~(tmp_termio.c_iflag & IXON) &&
	    (tty->termios->c_iflag & IXON))
	  {
	     tty->status_changed = 1;
	     tty->ctrl_status |= TIOCPKT_NOSTOP;
	  }

	*(unsigned short *)&tty->termios->c_iflag = tmp_termio.c_iflag;
	*(unsigned short *)&tty->termios->c_oflag = tmp_termio.c_oflag;
	*(unsigned short *)&tty->termios->c_cflag = tmp_termio.c_cflag;
	*(unsigned short *)&tty->termios->c_lflag = tmp_termio.c_lflag;
	tty->termios->c_line = tmp_termio.c_line;
	for(i=0 ; i < NCC ; i++)
		tty->termios->c_cc[i] = tmp_termio.c_cc[i];
	if (IS_A_SERIAL(channel) && tty->termios->c_cflag != old_cflag)
		change_speed(channel-64);
	return 0;
}
Пример #4
0
static int job_control(struct tty_struct *tty, struct file *file)
{
	/* Job control check -- must be done at start and after
	   every sleep (POSIX.1 7.1.1.4). */
	/* NOTE: not yet done after every sleep pending a thorough
	   check of the logic of this change. -- jlc */
	/* don't stop on /dev/console */
	if (file->f_op->write != redirected_tty_write &&
	    current->signal->tty == tty) {
		if (tty->pgrp <= 0)
			printk("read_chan: tty->pgrp <= 0!\n");
		else if (process_group(current) != tty->pgrp) {
			if (is_ignored(SIGTTIN) ||
			    is_orphaned_pgrp(process_group(current)))
				return -EIO;
			kill_pg(process_group(current), SIGTTIN, 1);
			return -ERESTARTSYS;
		}
	}
	return 0;
}
Пример #5
0
static int tty_read(struct inode * inode, struct file * file, char * buf, int count)
{
	int i, dev;
	struct tty_struct * tty;

	dev = file->f_rdev;
	if (MAJOR(dev) != TTY_MAJOR) {
		printk("tty_read: bad pseudo-major nr #%d\n", MAJOR(dev));
		return -EINVAL;
	}
	dev = MINOR(dev);
	tty = TTY_TABLE(dev);
	if (!tty || (tty->flags & (1 << TTY_IO_ERROR)))
		return -EIO;

	/* This check not only needs to be done before reading, but also
	   whenever read_chan() gets woken up after sleeping, so I've
	   moved it to there.  This should only be done for the N_TTY
	   line discipline, anyway.  Same goes for write_chan(). -- jlc. */
#if 0
	if ((inode->i_rdev != CONSOLE_DEV) && /* don't stop on /dev/console */
	    (tty->pgrp > 0) &&
	    (current->tty == dev) &&
	    (tty->pgrp != current->pgrp))
		if (is_ignored(SIGTTIN) || is_orphaned_pgrp(current->pgrp))
			return -EIO;
		else {
			(void) kill_pg(current->pgrp, SIGTTIN, 1);
			return -ERESTARTSYS;
		}
#endif
	if (ldiscs[tty->disc].read)
		/* XXX casts are for what kernel-wide prototypes should be. */
		i = (ldiscs[tty->disc].read)(tty,file,(unsigned char *)buf,(unsigned int)count);
	else
		i = -EIO;
	if (i > 0)
		inode->i_atime = CURRENT_TIME;
	return i;
}
Пример #6
0
static int job_control(struct tty_struct *tty, struct file *file)
{
	/* Job control check -- must be done at start and after
	   every sleep (POSIX.1 7.1.1.4). */
	/* NOTE: not yet done after every sleep pending a thorough
	   check of the logic of this change. -- jlc */
	/* don't stop on /dev/console */
	if (file->f_dentry->d_inode->i_rdev != CONSOLE_DEV &&
	    file->f_dentry->d_inode->i_rdev != SYSCONS_DEV &&
	    current->tty == tty) {
		if (tty->pgrp <= 0)
			printk("read_chan: tty->pgrp <= 0!\n");
		else if (current->pgrp != tty->pgrp) {
			if (is_ignored(SIGTTIN) ||
			    is_orphaned_pgrp(current->pgrp))
				return -EIO;
			kill_pg(current->pgrp, SIGTTIN, 1);
			return -ERESTARTSYS;
		}
	}
	return 0;
}
Пример #7
0
static int tty_write(struct inode * inode, struct file * file, char * buf, int count)
{
	int dev, i, is_console;
	struct tty_struct * tty;

	dev = file->f_rdev;
	is_console = (inode->i_rdev == CONSOLE_DEV);
	if (MAJOR(dev) != TTY_MAJOR) {
		printk("tty_write: pseudo-major != TTY_MAJOR\n");
		return -EINVAL;
	}
	dev = MINOR(dev);
	if (is_console && redirect)
		tty = redirect;
	else
		tty = TTY_TABLE(dev);
	if (!tty || !tty->write || (tty->flags & (1 << TTY_IO_ERROR)))
		return -EIO;
#if 0
	if (!is_console && L_TOSTOP(tty) && (tty->pgrp > 0) &&
	    (current->tty == dev) && (tty->pgrp != current->pgrp)) {
		if (is_orphaned_pgrp(current->pgrp))
			return -EIO;
		if (!is_ignored(SIGTTOU)) {
			(void) kill_pg(current->pgrp, SIGTTOU, 1);
			return -ERESTARTSYS;
		}
	}
#endif
	if (ldiscs[tty->disc].write)
		/* XXX casts are for what kernel-wide prototypes should be. */
		i = (ldiscs[tty->disc].write)(tty,file,(unsigned char *)buf,(unsigned int)count);
	else
		i = -EIO;
	if (i > 0)
		inode->i_mtime = CURRENT_TIME;
	return i;
}
Пример #8
0
volatile void do_exit(long code)
{
	struct task_struct *p;
	int i;

fake_volatile:
	free_page_tables(current);
	for (i=0 ; i<NR_OPEN ; i++)
		if (current->filp[i])
			sys_close(i);
	forget_original_parent(current);
	iput(current->pwd);
	current->pwd = NULL;
	iput(current->root);
	current->root = NULL;
	iput(current->executable);
	current->executable = NULL;
	for (i=0; i < current->numlibraries; i++) {
		iput(current->libraries[i].library);
		current->libraries[i].library = NULL;
	}	
	current->state = TASK_ZOMBIE;
	current->exit_code = code;
	current->rss = 0;
	/* 
	 * Check to see if any process groups have become orphaned
	 * as a result of our exiting, and if they have any stopped
	 * jobs, send them a SIGUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 *
	 * Case i: Our father is in a different pgrp than we are
	 * and we were the only connection outside, so our pgrp
	 * is about to become orphaned.
 	 */
	if ((current->p_pptr->pgrp != current->pgrp) &&
	    (current->p_pptr->session == current->session) &&
	    is_orphaned_pgrp(current->pgrp) &&
	    has_stopped_jobs(current->pgrp)) {
		kill_pg(current->pgrp,SIGHUP,1);
		kill_pg(current->pgrp,SIGCONT,1);
	}
	/* Let father know we died */
	send_sig (SIGCHLD, current->p_pptr, 1);
	
	/*
	 * This loop does two things:
	 * 
  	 * A.  Make init inherit all the child processes
	 * B.  Check to see if any process groups have become orphaned
	 *	as a result of our exiting, and if they have any stopped
	 *	jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 */
	while ((p = current->p_cptr) != NULL) {
		current->p_cptr = p->p_osptr;
		p->p_ysptr = NULL;
		p->flags &= ~(PF_PTRACED|PF_TRACESYS);
		if (task[1])
			p->p_pptr = task[1];
		else
			p->p_pptr = task[0];
		p->p_osptr = p->p_pptr->p_cptr;
		p->p_osptr->p_ysptr = p;
		p->p_pptr->p_cptr = p;
		if (p->state == TASK_ZOMBIE)
			send_sig(SIGCHLD,p->p_pptr,1);
		/*
		 * process group orphan check
		 * Case ii: Our child is in a different pgrp 
		 * than we are, and it was the only connection
		 * outside, so the child pgrp is now orphaned.
		 */
		if ((p->pgrp != current->pgrp) &&
		    (p->session == current->session) &&
		    is_orphaned_pgrp(p->pgrp) &&
		    has_stopped_jobs(p->pgrp)) {
			kill_pg(p->pgrp,SIGHUP,1);
			kill_pg(p->pgrp,SIGCONT,1);
		}
	}
	if (current->leader) {
		struct task_struct **p;
		struct tty_struct *tty;

		if (current->tty >= 0) {
			tty = TTY_TABLE(current->tty);
			if (tty) {
				if (tty->pgrp > 0)
					kill_pg(tty->pgrp, SIGHUP, 1);
				tty->pgrp = -1;
				tty->session = 0;
			}
		}
	 	for (p = &LAST_TASK ; p > &FIRST_TASK ; --p)
			if (*p && (*p)->session == current->session)
				(*p)->tty = -1;
	}
	if (last_task_used_math == current)
		last_task_used_math = NULL;
#ifdef DEBUG_PROC_TREE
	audit_ptree();
#endif
	schedule();
/*
 * In order to get rid of the "volatile function does return" message
 * I did this little loop that confuses gcc to think do_exit really
 * is volatile. In fact it's schedule() that is volatile in some
 * circumstances: when current->state = ZOMBIE, schedule() never
 * returns.
 *
 * In fact the natural way to do all this is to have the label and the
 * goto right after each other, but I put the fake_volatile label at
 * the start of the function just in case something /really/ bad
 * happens, and the schedule returns. This way we can try again. I'm
 * not paranoid: it's just that everybody is out to get me.
 */
	goto fake_volatile;
}
Пример #9
0
/*
 * Send signals to all our closest relatives so that they know
 * to properly mourn us..
 */
static void exit_notify(void)
{
	struct task_struct * p, *t;

	forget_original_parent(current);
	/*
	 * Check to see if any process groups have become orphaned
	 * as a result of our exiting, and if they have any stopped
	 * jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 *
	 * Case i: Our father is in a different pgrp than we are
	 * and we were the only connection outside, so our pgrp
	 * is about to become orphaned.
	 */
	 
	t = current->p_pptr;
	
	if ((t->pgrp != current->pgrp) &&
	    (t->session == current->session) &&
	    will_become_orphaned_pgrp(current->pgrp, current) &&
	    has_stopped_jobs(current->pgrp)) {
		kill_pg(current->pgrp,SIGHUP,1);
		kill_pg(current->pgrp,SIGCONT,1);
	}

	/* Let father know we died 
	 *
	 * Thread signals are configurable, but you aren't going to use
	 * that to send signals to arbitary processes. 
	 * That stops right now.
	 *
	 * If the parent exec id doesn't match the exec id we saved
	 * when we started then we know the parent has changed security
	 * domain.
	 *
	 * If our self_exec id doesn't match our parent_exec_id then
	 * we have changed execution domain as these two values started
	 * the same after a fork.
	 *	
	 */
	
	if (current->exit_signal && current->exit_signal != SIGCHLD &&
	    ( current->parent_exec_id != t->self_exec_id  ||
	      current->self_exec_id != current->parent_exec_id))
		current->exit_signal = SIGCHLD;


	/*
	 * This loop does two things:
	 *
  	 * A.  Make init inherit all the child processes
	 * B.  Check to see if any process groups have become orphaned
	 *	as a result of our exiting, and if they have any stopped
	 *	jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 */

	write_lock_irq(&tasklist_lock);
	current->state = TASK_ZOMBIE;
	do_notify_parent(current, current->exit_signal);
	while (current->p_cptr != NULL) {
		p = current->p_cptr;
		current->p_cptr = p->p_osptr;
		p->p_ysptr = NULL;
		p->ptrace = 0;

		p->p_pptr = p->p_opptr;
		p->p_osptr = p->p_pptr->p_cptr;
		if (p->p_osptr)
			p->p_osptr->p_ysptr = p;
		p->p_pptr->p_cptr = p;
		if (p->state == TASK_ZOMBIE)
			do_notify_parent(p, p->exit_signal);
		/*
		 * process group orphan check
		 * Case ii: Our child is in a different pgrp
		 * than we are, and it was the only connection
		 * outside, so the child pgrp is now orphaned.
		 */
		if ((p->pgrp != current->pgrp) &&
		    (p->session == current->session)) {
			int pgrp = p->pgrp;

			write_unlock_irq(&tasklist_lock);
			if (is_orphaned_pgrp(pgrp) && has_stopped_jobs(pgrp)) {
				kill_pg(pgrp,SIGHUP,1);
				kill_pg(pgrp,SIGCONT,1);
			}
			write_lock_irq(&tasklist_lock);
		}
	}
	write_unlock_irq(&tasklist_lock);
}
Пример #10
0
/*
 * 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.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 *
 * "r0" and "r19" are the registers we need to restore for system call
 * restart. "r0" is also used as an indicator whether we can restart at
 * all (if we get here from anything but a syscall return, it will be 0)
 */
asmlinkage int
do_signal(sigset_t *oldset, struct pt_regs * regs, struct switch_stack * sw,
          unsigned long r0, unsigned long r19)
{
    unsigned long single_stepping = ptrace_cancel_bpt(current);

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

    while (1) {
        unsigned long signr;
        struct k_sigaction *ka;
        siginfo_t info;

        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();
            single_stepping |= ptrace_cancel_bpt(current);

            /* 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 & 0x7f;

            /* 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();
                single_stepping |= ptrace_cancel_bpt(current);
                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();
                sigaddset(&current->pending.signal, signr);
                current->flags |= PF_SIGNALED;
                do_exit(exit_code);
                /* NOTREACHED */
            }
            continue;
        }

        /* Whee!  Actually deliver the signal.  */
        if (r0) syscall_restart(r0, r19, regs, ka);
        handle_signal(signr, ka, &info, oldset, regs, sw);
        if (single_stepping)
            ptrace_set_bpt(current); /* re-set bpt */
        return 1;
    }

    if (r0 &&
            (regs->r0 == ERESTARTNOHAND ||
             regs->r0 == ERESTARTSYS ||
             regs->r0 == ERESTARTNOINTR)) {
        regs->r0 = r0;	/* reset v0 and a3 and replay syscall */
        regs->r19 = r19;
        regs->pc -= 4;
    }
    if (single_stepping)
        ptrace_set_bpt(current);	/* re-set breakpoint */

    return 0;
}
Пример #11
0
/*
 * 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.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 */
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
{
	struct k_sigaction *ka;
	siginfo_t info;
	int single_stepping;

	/*
	 * 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 0;

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

	single_stepping = ptrace_cancel_bpt(current);

	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();
			single_stepping |= ptrace_cancel_bpt(current);

			/* 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: case SIGURG:
				continue;

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

			case SIGSTOP: {
				struct signal_struct *sig;
				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();
				single_stepping |= ptrace_cancel_bpt(current);
				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 */
			}
		}

		/* Are we from a system call? */
		if (syscall) {
			switch (regs->ARM_r0) {
			case -ERESTARTNOHAND:
				regs->ARM_r0 = -EINTR;
				break;

			case -ERESTARTSYS:
				if (!(ka->sa.sa_flags & SA_RESTART)) {
					regs->ARM_r0 = -EINTR;
					break;
				}
				/* fallthrough */
			case -ERESTARTNOINTR:
				restart_syscall(regs);
				break;


			}
		}
		/* Whee!  Actually deliver the signal.  */
		handle_signal(signr, ka, &info, oldset, regs);
		if (single_stepping)
		    	ptrace_set_bpt(current);
		return 1;
	}

	if (syscall &&
	    (regs->ARM_r0 == -ERESTARTNOHAND ||
	     regs->ARM_r0 == -ERESTARTSYS ||
	     regs->ARM_r0 == -ERESTARTNOINTR)) {
		restart_syscall(regs);
	}

	if (single_stepping)
		ptrace_set_bpt(current);
	return 0;
}
Пример #12
0
/*
 * 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.
 *
 * Note that we go through the signals twice: once to check the signals that
 * the kernel can handle, and then we build all the user-level signal handling
 * stack-frames in one go after that.
 */
int do_signal(struct pt_regs *regs, sigset_t *oldset)
{
	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:
				sigaddset(&current->pending.signal, signr);
				recalc_sigpending(current);
				current->flags |= PF_SIGNALED;
				do_exit(exit_code);
				/* NOTREACHED */
			}
		}

		/* Whee!  Actually deliver the signal.  */
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	/* Did we come from a system call? */
	if (PT_REGS_SYSCALL (regs)) {
		/* Restart the system call - no handlers present */
		if (regs->gpr[GPR_RVAL] == -ERESTARTNOHAND ||
		    regs->gpr[GPR_RVAL] == -ERESTARTSYS ||
		    regs->gpr[GPR_RVAL] == -ERESTARTNOINTR) {
			regs->gpr[12] = PT_REGS_SYSCALL (regs);
			regs->pc -= 8; /* 4 + 8 for microblaze return offset wierdness */
		}
	}
	return 0;
}
Пример #13
0
/*
 * 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;
}
Пример #14
0
static int
get_signal_to_deliver(siginfo_t *info, struct pt_regs *regs)
{
	for (;;) {
		unsigned long signr;
		struct k_sigaction *ka;

		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?  */
			signr = current->exit_code;
			if (signr == 0)
				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: {
				struct signal_struct *sig;
				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, regs))
					exit_code |= 0x80;
				/* FALLTHRU */

			default:
				sig_exit(signr, exit_code, info);
				/* NOTREACHED */
			}
		}
		return signr;
	}
	return 0;
}
Пример #15
0
int do_signal(struct pt_regs *regs, sigset_t *oldset)
{
	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 ((regs->xcs & 3) != 3)
		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;

		/* We should probably find a better way to do this. */
		if(ssmunch_multi) {
			int i;

			/* Here's a hack.  If we get a signal that's not
			 * one of the signals sent by ssmunch, then
			 * we won't print a message, since the ssmunch'd
			 * process is probably dead or mostly dead.
			 * Mostly dead is not quite the same as dead; for more
			 * information on this topic please see Miracle Max.
			 */
			for(i = 0; i < 32; i++) {
				if(ssmunch_multi&(1<<i)) break;
			}
			if(i == 32) goto no_ssmunch;
			/* HAHA!    ^^^^ I used a goto!  Now I'm a real
			 * kernel h4x0r!
			 */

			printk("do_signal: multiple signals: ");
			for(i = 0; i < 32; i++) {
				if(ssmunch_multi&(1<<i)) printk("%d ", i);
			}
			printk("\n");

no_ssmunch:
			ssmunch_multi = 0;
		}

		if ((current->flags & PF_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:
				lock_kernel();
				if (current->binfmt
				    && current->binfmt->core_dump
				    && current->binfmt->core_dump(signr, regs))
					exit_code |= 0x80;
				unlock_kernel();
				/* FALLTHRU */

			default:
				lock_kernel();
				sigaddset(&current->signal, signr);
				recalc_sigpending(current);
				current->flags |= PF_SIGNALED;
				/*
				printk("do_signal: do_exit with %d\n",
					exit_code);
				*/
				do_exit(exit_code);
				/* NOTREACHED */
			}
		}

		/* Whee!  Actually deliver the signal.  */
		/*
		printk("do_signal: handle_signal with %d\n", signr);
		*/
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	/* Did we come from a system call? */
	if (regs->orig_eax >= 0) {
		/* Restart the system call - no handlers present */
		if (regs->eax == -ERESTARTNOHAND ||
		    regs->eax == -ERESTARTSYS ||
		    regs->eax == -ERESTARTNOINTR) {
			regs->eax = regs->orig_eax;
			regs->eip -= 2;
		}
	}
	return 0;
}
Пример #16
0
/*
 * 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.
 *
 * Note that we go through the signals twice: once to check the signals
 * that the kernel can handle, and then we build all the user-level signal
 * handling stack-frames in one go after that.
 */
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	siginfo_t info;
	struct k_sigaction *ka;

	current->thread.esp0 = (unsigned long) regs;

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

	for (;;) {
		int signr;

		signr = get_signal_to_deliver(&info, regs, NULL);

		if (!signr)
			break;

		if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
			current->exit_code = signr;
			current->state = TASK_STOPPED;

			/* Did we come from a system call? */
			if (regs->orig_er0 >= 0) {
				/* Restart the system call the same way as
				   if the process were not traced.  */
				struct k_sigaction *ka =
					&current->sighand->action[signr-1];
				int has_handler =
					(ka->sa.sa_handler != SIG_IGN &&
					 ka->sa.sa_handler != SIG_DFL);
				handle_restart(regs, ka, has_handler);
			}
			notify_parent(current, SIGCHLD);
			schedule();

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

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

			/* 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->parent->pid;
				info.si_uid = current->parent->uid;
			}

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

		ka = &current->sighand->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;

			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(process_group(current)))
					continue;
				/* FALLTHRU */

			case SIGSTOP: {
				struct sighand_struct *sig;
				current->state = TASK_STOPPED;
				current->exit_code = signr;
                                sig = current->parent->sighand;
                                if (sig && !(sig->action[SIGCHLD-1].sa.sa_flags 
& SA_NOCLDSTOP))
                                        notify_parent(current, SIGCHLD);
				schedule();
				continue;
			}

			case SIGQUIT: case SIGILL: case SIGTRAP:
			case SIGIOT: case SIGFPE: case SIGSEGV:
			case SIGBUS: case SIGSYS: case SIGXCPU: case SIGXFSZ:
				if (do_coredump(signr, exit_code, regs))
					exit_code |= 0x80;
				/* FALLTHRU */

			default:
				sigaddset(&current->pending.signal, signr);
				recalc_sigpending();
				current->flags |= PF_SIGNALED;
				do_exit(exit_code);
				/* NOTREACHED */
			}
		}

		/* Whee!  Actually deliver the signal.  */
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	/* Did we come from a system call? */
	if (regs->orig_er0 >= 0)
		/* Restart the system call - no handlers present */
		handle_restart(regs, NULL, 0);

	return 0;
}
Пример #17
0
static void copy_to_cooked(struct tty_struct * tty)
{
	int c, special_flag;
	unsigned long flags;

	if (!tty) {
		printk("copy_to_cooked: called with NULL tty\n");
		return;
	}
	if (!tty->write) {
		printk("copy_to_cooked: tty %d has null write routine\n",
		       tty->line);
	}
	while (1) {
		/*
		 * Check to see how much room we have left in the
		 * secondary queue.  Send a throttle command or abort
		 * if necessary.
		 */
		c = LEFT(&tty->secondary);
		if (tty->throttle && (c < SQ_THRESHOLD_LW)
		    && !set_bit(TTY_SQ_THROTTLED, &tty->flags))
			tty->throttle(tty, TTY_THROTTLE_SQ_FULL);
		if (c == 0)
			break;
		save_flags(flags); cli();
		if (!EMPTY(&tty->read_q)) {
			c = tty->read_q.buf[tty->read_q.tail];
			special_flag = clear_bit(tty->read_q.tail,
						 &tty->readq_flags);
			INC(tty->read_q.tail);
			restore_flags(flags);
		} else {
			restore_flags(flags);
			break;
		}
		if (special_flag) {
			tty->char_error = c;
			continue;
		}
		if (tty->char_error) {
			if (tty->char_error == TTY_BREAK) {
				tty->char_error = 0;
				if (I_IGNBRK(tty))
					continue;
				/* A break is handled by the lower levels. */
				if (I_BRKINT(tty))
					continue;
				if (I_PARMRK(tty)) {
					put_tty_queue('\377', &tty->secondary);
					put_tty_queue('\0', &tty->secondary);
				}
				put_tty_queue('\0', &tty->secondary);
				continue;
			}
			if (tty->char_error == TTY_OVERRUN) {
				tty->char_error = 0;
				printk("tty%d: input overrun\n", tty->line);
				continue;
			}
			/* Must be a parity or frame error */
			tty->char_error = 0;
			if (I_IGNPAR(tty)) {
				continue;
			}
			if (I_PARMRK(tty)) {
				put_tty_queue('\377', &tty->secondary);
				put_tty_queue('\0', &tty->secondary);
				put_tty_queue(c, &tty->secondary);
			} else
				put_tty_queue('\0', &tty->secondary);
			continue;
		}
		if (I_ISTRIP(tty))
			c &= 0x7f;
		if (!tty->lnext) {
			if (c == '\r') {
				if (I_IGNCR(tty))
					continue;
				if (I_ICRNL(tty))
					c = '\n';
			} else if (c == '\n' && I_INLCR(tty))
				c = '\r';
		}
		if (I_IUCLC(tty) && L_IEXTEN(tty))
			c=tolower(c);
		if (c == __DISABLED_CHAR)
			tty->lnext = 1;
		if (L_ICANON(tty) && !tty->lnext) {
			if (c == ERASE_CHAR(tty) || c == KILL_CHAR(tty) ||
			    (c == WERASE_CHAR(tty) && L_IEXTEN(tty))) {
				eraser(c, tty);
				continue;
			}
			if (c == LNEXT_CHAR(tty) && L_IEXTEN(tty)) {
				tty->lnext = 1;
				if (L_ECHO(tty)) {
					if (tty->erasing) {
						opost('/', tty);
						tty->erasing = 0;
					}
					if (L_ECHOCTL(tty)) {
						opost('^', tty);
						opost('\b', tty);
					}
				}
				continue;
			}
			if (c == REPRINT_CHAR(tty) && L_ECHO(tty) &&
			    L_IEXTEN(tty)) {
				unsigned long tail = tty->canon_head;

				if (tty->erasing) {
					opost('/', tty);
					tty->erasing = 0;
				}
				echo_char(c, tty);
				opost('\n', tty);
				while (tail != tty->secondary.head) {
					echo_char(tty->secondary.buf[tail],
						  tty);
					INC(tail);
				}
				continue;
			}
		}
		if (I_IXON(tty) && !tty->lnext) {
			if ((tty->stopped && I_IXANY(tty) && L_IEXTEN(tty)) ||
			    c == START_CHAR(tty)) {
				start_tty(tty);
				continue;
			}
			if (c == STOP_CHAR(tty)) {
				stop_tty(tty);
				continue;
			}
		}
		if (L_ISIG(tty) && !tty->lnext) {
			if (c == INTR_CHAR(tty)) {
				isig(SIGINT, tty);
				continue;
			}
			if (c == QUIT_CHAR(tty)) {
				isig(SIGQUIT, tty);
				continue;
			}
			if (c == SUSP_CHAR(tty)) {
				if (!is_orphaned_pgrp(tty->pgrp))
					isig(SIGTSTP, tty);
				continue;
			}
		}

		if (tty->erasing) {
			opost('/', tty);
			tty->erasing = 0;
		}
		if (c == '\n' && !tty->lnext) {
			if (L_ECHO(tty) || (L_ICANON(tty) && L_ECHONL(tty)))
				opost('\n', tty);
		} else if (L_ECHO(tty)) {
			/* Don't echo the EOF char in canonical mode.  Sun
			   handles this differently by echoing the char and
			   then backspacing, but that's a hack. */
			if (c != EOF_CHAR(tty) || !L_ICANON(tty) ||
			    tty->lnext) {
				/* Record the column of first canon char. */
				if (tty->canon_head == tty->secondary.head)
					tty->canon_column = tty->column;
				echo_char(c, tty);
			}
		}

		if (I_PARMRK(tty) && c == (unsigned char) '\377' &&
		    (c != EOF_CHAR(tty) || !L_ICANON(tty) || tty->lnext))
			put_tty_queue(c, &tty->secondary);

		if (L_ICANON(tty) && !tty->lnext &&
		    (c == '\n' || c == EOF_CHAR(tty) || c == EOL_CHAR(tty) ||
		     (c == EOL2_CHAR(tty) && L_IEXTEN(tty)))) {
			if (c == EOF_CHAR(tty))
				c = __DISABLED_CHAR;
			set_bit(tty->secondary.head, &tty->secondary_flags);
			put_tty_queue(c, &tty->secondary);
			tty->canon_head = tty->secondary.head;
			tty->canon_data++;
		} else
			put_tty_queue(c, &tty->secondary);
		tty->lnext = 0;
	}
	if (!EMPTY(&tty->write_q))
		TTY_WRITE_FLUSH(tty);
	if (L_ICANON(tty) ? tty->canon_data : !EMPTY(&tty->secondary))
		wake_up_interruptible(&tty->secondary.proc_list);

	if (tty->throttle && (LEFT(&tty->read_q) >= RQ_THRESHOLD_HW)
	    && clear_bit(TTY_RQ_THROTTLED, &tty->flags))
		tty->throttle(tty, TTY_THROTTLE_RQ_AVAIL);
}
Пример #18
0
static ssize_t read_chan(struct tty_struct *tty, struct file *file,
			 unsigned char *buf, size_t nr)
{
	unsigned char *b = buf;
	struct wait_queue wait = { current, NULL };
	int c;
	int minimum, time;
	ssize_t retval = 0;
	ssize_t size;
	long timeout;

do_it_again:

	if (!tty->read_buf) {
		printk("n_tty_read_chan: called with read_buf == NULL?!?\n");
		return -EIO;
	}

	/* Job control check -- must be done at start and after
	   every sleep (POSIX.1 7.1.1.4). */
	/* NOTE: not yet done after every sleep pending a thorough
	   check of the logic of this change. -- jlc */
	/* don't stop on /dev/console */
	if (file->f_dentry->d_inode->i_rdev != CONSOLE_DEV &&
	    file->f_dentry->d_inode->i_rdev != SYSCONS_DEV &&
	    current->tty == tty) {
		if (tty->pgrp <= 0)
			printk("read_chan: tty->pgrp <= 0!\n");
		else if (current->pgrp != tty->pgrp) {
			if (is_ignored(SIGTTIN) ||
			    is_orphaned_pgrp(current->pgrp))
				return -EIO;
			kill_pg(current->pgrp, SIGTTIN, 1);
			return -ERESTARTSYS;
		}
	}

	minimum = time = 0;
	timeout = MAX_SCHEDULE_TIMEOUT;
	if (!tty->icanon) {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum) {
			if (time)
				tty->minimum_to_wake = 1;
			else if (!waitqueue_active(&tty->read_wait) ||
				 (tty->minimum_to_wake > minimum))
				tty->minimum_to_wake = minimum;
		} else {
			timeout = 0;
			if (time) {
				timeout = time;
				time = 0;
			}
			tty->minimum_to_wake = minimum = 1;
		}
	}

	if (file->f_flags & O_NONBLOCK) {
		if (down_trylock(&tty->atomic_read))
			return -EAGAIN;
	}
	else {
		if (down_interruptible(&tty->atomic_read))
			return -ERESTARTSYS;
	}

	add_wait_queue(&tty->read_wait, &wait);
	set_bit(TTY_DONT_FLIP, &tty->flags);
	while (nr) {
		/* First test for status change. */
		if (tty->packet && tty->link->ctrl_status) {
			unsigned char cs;
			if (b != buf)
				break;
			cs = tty->link->ctrl_status;
			tty->link->ctrl_status = 0;
			put_user(cs, b++);
			nr--;
			break;
		}
		/* This statement must be first before checking for input
		   so that any interrupt will set the state back to
		   TASK_RUNNING. */
		current->state = TASK_INTERRUPTIBLE;
		
		if (((minimum - (b - buf)) < tty->minimum_to_wake) &&
		    ((minimum - (b - buf)) >= 1))
			tty->minimum_to_wake = (minimum - (b - buf));
		
		if (!input_available_p(tty, 0)) {
			if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (signal_pending(current)) {
				retval = -ERESTARTSYS;
				break;
			}
			clear_bit(TTY_DONT_FLIP, &tty->flags);
			timeout = schedule_timeout(timeout);
			set_bit(TTY_DONT_FLIP, &tty->flags);
			continue;
		}
		current->state = TASK_RUNNING;

		/* Deal with packet mode. */
		if (tty->packet && b == buf) {
			put_user(TIOCPKT_DATA, b++);
			nr--;
		}

		if (tty->icanon) {
			/* N.B. avoid overrun if nr == 0 */
			while (nr && tty->read_cnt) {
 				int eol;

				eol = test_and_clear_bit(tty->read_tail,
						&tty->read_flags);
				c = tty->read_buf[tty->read_tail];
				tty->read_tail = ((tty->read_tail+1) &
						  (N_TTY_BUF_SIZE-1));
				tty->read_cnt--;

				if (!eol || (c != __DISABLED_CHAR)) {
					put_user(c, b++);
					nr--;
				}
				if (eol) {
					/* this test should be redundant:
					 * we shouldn't be reading data if
					 * canon_data is 0
					 */
					if (--tty->canon_data < 0)
						tty->canon_data = 0;
					break;
				}
			}
		} else {
			int uncopied;
			uncopied = copy_from_read_buf(tty, &b, &nr);
			uncopied += copy_from_read_buf(tty, &b, &nr);
			if (uncopied) {
				retval = -EFAULT;
				break;
			}
		}

		/* If there is enough space in the read buffer now, let the
		 * low-level driver know. We use n_tty_chars_in_buffer() to
		 * check the buffer, as it now knows about canonical mode.
		 * Otherwise, if the driver is throttled and the line is
		 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
		 * we won't get any more characters.
		 */
		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE)
			check_unthrottle(tty);

		if (b - buf >= minimum)
			break;
		if (time)
			timeout = time;
	}
	clear_bit(TTY_DONT_FLIP, &tty->flags);
	up(&tty->atomic_read);
	remove_wait_queue(&tty->read_wait, &wait);

	if (!waitqueue_active(&tty->read_wait))
		tty->minimum_to_wake = minimum;

	current->state = TASK_RUNNING;
	size = b - buf;
	if (size) {
		retval = size;
		if (nr)
	       		clear_bit(TTY_PUSH, &tty->flags);
	} else if (test_and_clear_bit(TTY_PUSH, &tty->flags))
		 goto do_it_again;

	return retval;
}
Пример #19
0
static int read_chan(struct tty_struct *tty, struct file *file,
		     unsigned char *buf, unsigned int nr)
{
	struct wait_queue wait = { current, NULL };
	int c;
	unsigned char *b = buf;
	int minimum, time;
	int retval = 0;

	/* Job control check -- must be done at start and after
	   every sleep (POSIX.1 7.1.1.4). */
	/* NOTE: not yet done after every sleep pending a thorough
	   check of the logic of this change. -- jlc */
	/* don't stop on /dev/console */
	if (file->f_inode->i_rdev != CONSOLE_DEV &&
	    current->tty == tty->line) {
		if (tty->pgrp <= 0)
			printk("read_chan: tty->pgrp <= 0!\n");
		else if (current->pgrp != tty->pgrp) {
			if (is_ignored(SIGTTIN) ||
			    is_orphaned_pgrp(current->pgrp))
				return -EIO;
			kill_pg(current->pgrp, SIGTTIN, 1);
			return -ERESTARTSYS;
		}
	}

	if (L_ICANON(tty)) {
		minimum = time = 0;
		current->timeout = (unsigned long) -1;
	} else {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum)
		  	current->timeout = (unsigned long) -1;
		else {
			if (time) {
				current->timeout = time + jiffies;
				time = 0;
			} else
				current->timeout = 0;
			minimum = 1;
		}
	}

	add_wait_queue(&tty->secondary.proc_list, &wait);
	while (1) {
		/* First test for status change. */
		if (tty->packet && tty->link->ctrl_status) {
			if (b != buf)
				break;
			put_fs_byte(tty->link->ctrl_status, b++);
			tty->link->ctrl_status = 0;
			break;
		}
		/* This statement must be first before checking for input
		   so that any interrupt will set the state back to
		   TASK_RUNNING. */
		current->state = TASK_INTERRUPTIBLE;
		if (!input_available_p(tty)) {
			if (tty->flags & (1 << TTY_SLAVE_CLOSED)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!current->timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (current->signal & ~current->blocked) {
				retval = -ERESTARTSYS;
				break;
			}
			schedule();
			continue;
		}
		current->state = TASK_RUNNING;

		/* Deal with packet mode. */
		if (tty->packet && b == buf) {
			put_fs_byte(TIOCPKT_DATA, b++);
			nr--;
		}

		while (1) {
			int eol;

			cli();
			if (EMPTY(&tty->secondary)) {
				sti();
				break;
			}
			eol = clear_bit(tty->secondary.tail,
					&tty->secondary_flags);
			c = tty->secondary.buf[tty->secondary.tail];
			if (!nr) {
				/* Gobble up an immediately following EOF if
				   there is no more room in buf (this can
				   happen if the user "pushes" some characters
				   using ^D).  This prevents the next read()
				   from falsely returning EOF. */
				if (eol) {
					if (c == __DISABLED_CHAR) {
						tty->canon_data--;
						INC(tty->secondary.tail);
					} else {
						set_bit(tty->secondary.tail,
							&tty->secondary_flags);
					}
				}
				sti();
				break;
			}
			INC(tty->secondary.tail);
			sti();
			if (eol) {
				if (--tty->canon_data < 0) {
					printk("read_chan: canon_data < 0!\n");
					tty->canon_data = 0;
				}
				if (c == __DISABLED_CHAR)
					break;
				put_fs_byte(c, b++);
				nr--;
				break;
			}
			put_fs_byte(c, b++);
			nr--;
		}

		/* If there is enough space in the secondary queue now, let the
		   low-level driver know. */
		if (tty->throttle && (LEFT(&tty->secondary) >= SQ_THRESHOLD_HW)
		    && clear_bit(TTY_SQ_THROTTLED, &tty->flags))
			tty->throttle(tty, TTY_THROTTLE_SQ_AVAIL);

		if (b - buf >= minimum || !nr)
			break;
		if (time)
			current->timeout = time + jiffies;
	}
	remove_wait_queue(&tty->secondary.proc_list, &wait);
	current->state = TASK_RUNNING;
	current->timeout = 0;
	return (b - buf) ? b - buf : retval;
}
Пример #20
0
asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)
{
	struct k_sigaction *ka;
	siginfo_t info;

	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:
				if (do_coredump(signr, regs))
					exit_code |= 0x80;
				/* FALLTHRU */

			default:
				sigaddset(&current->pending.signal, signr);
				recalc_sigpending(current);
				current->flags |= PF_SIGNALED;
				do_exit(exit_code);
				/* NOTREACHED */
			}
		}

		if (regs->regs[0])
			syscall_restart(regs, ka);
		/* Whee!  Actually deliver the signal.  */
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}

	/*
	 * Who's code doesn't conform to the restartable syscall convention
	 * dies here!!!  The li instruction, a single machine instruction,
	 * must directly be followed by the syscall instruction.
	 */
	if (regs->regs[0]) {
		if (regs->regs[2] == ERESTARTNOHAND ||
		    regs->regs[2] == ERESTARTSYS ||
		    regs->regs[2] == ERESTARTNOINTR) {
			regs->cp0_epc -= 8;
		}
	}
	return 0;
}
Пример #21
0
/*
 * 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.
 *
 * Note that we go through the signals twice: once to check the signals
 * that the kernel can handle, and then we build all the user-level signal
 * handling stack-frames in one go after that.
 */
asmlinkage int do_signal(unsigned long oldmask, struct pt_regs *regs)
{
	unsigned long mask = ~current->blocked;
	unsigned long signr;
	struct sigaction * sa;

	current->tss.esp0 = (unsigned long) regs;

	/* If the process is traced, all signals are passed to the debugger. */
	if (current->flags & PF_PTRACED)
		mask = ~0UL;
	while ((signr = current->signal & mask) != 0) {
                signr = ffz(~signr);
                clear_bit(signr, &current->signal);
		sa = current->sig->action + signr;
		signr++;

#ifdef DEBUG
		printk("Signal %d: ", sa->sa_handler);
#endif

		if ((current->flags & PF_PTRACED) && signr != SIGKILL) {
			current->exit_code = signr;
			current->state = TASK_STOPPED;

			/* Did we come from a system call? */
			if (regs->orig_d0 >= 0) {
				/* Restart the system call */
				if (regs->d0 == -ERESTARTNOHAND ||
				    regs->d0 == -ERESTARTSYS ||
				    regs->d0 == -ERESTARTNOINTR) {
					regs->d0 = regs->orig_d0;
					regs->pc -= 2;
				}
			}
			notify_parent(current, SIGCHLD);
			schedule();
			if (!(signr = current->exit_code)) {
			discard_frame:
			    continue;
			}
			current->exit_code = 0;
			if (signr == SIGSTOP)
				goto discard_frame;
			if (_S(signr) & current->blocked) {
				current->signal |= _S(signr);
				mask &= ~_S(signr);
				continue;
			}
			sa = current->sig->action + signr - 1;
		}
		if (sa->sa_handler == SIG_IGN) {
#ifdef DEBUG
			printk("Ignoring.\n");
#endif
			if (signr != SIGCHLD)
				continue;
			/* check for SIGCHLD: it's special */
			while (sys_waitpid(-1,NULL,WNOHANG) > 0)
				/* nothing */;
			continue;
		}
		if (sa->sa_handler == SIG_DFL) {
#ifdef DEBUG
			printk("Default.\n");
#endif
			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;
			case SIGSTOP:
				if (current->flags & PF_PTRACED)
					continue;
				current->state = TASK_STOPPED;
				current->exit_code = signr;
				if (!(current->p_pptr->sig->action[SIGCHLD-1].sa_flags & 
				      SA_NOCLDSTOP))
					notify_parent(current, SIGCHLD);
				schedule();
				continue;

			case SIGQUIT: case SIGILL: case SIGTRAP:
			case SIGIOT: case SIGFPE: case SIGSEGV:
				if (current->binfmt && current->binfmt->core_dump) {
				    if (current->binfmt->core_dump(signr, regs))
					signr |= 0x80;
				}
				/* fall through */
			default:
				current->signal |= _S(signr & 0x7f);
				current->flags |= PF_SIGNALED;
				do_exit(signr);
			}
		}
		handle_signal(signr, sa, oldmask, regs);
		return 1;
	}

	/* Did we come from a system call? */
	if (regs->orig_d0 >= 0) {
		/* Restart the system call - no handlers present */
		if (regs->d0 == -ERESTARTNOHAND ||
		    regs->d0 == -ERESTARTSYS ||
		    regs->d0 == -ERESTARTNOINTR) {
			regs->d0 = regs->orig_d0;
			regs->pc -= 2;
		}
	}

	/* If we are about to discard some frame stuff we must copy
	   over the remaining frame. */
	if (regs->stkadj) {
		struct pt_regs *tregs =
		  (struct pt_regs *) ((ulong) regs + regs->stkadj);
#if defined(DEBUG) || 1
	printk("!!!!!!!!!!!!!! stkadj !!!\n");
#endif
		/* This must be copied with decreasing addresses to
		   handle overlaps.  */
		tregs->pc = regs->pc;
		tregs->sr = regs->sr;
	}
	return 0;
}
Пример #22
0
NORET_TYPE void do_exit(long code)
{
	struct task_struct *p;
	int i;

fake_volatile:
	if (current->semun)
		sem_exit();
	if (current->shm)
		shm_exit();
	free_page_tables(current);
	for (i=0 ; i<NR_OPEN ; i++)
		if (current->filp[i])
			sys_close(i);
	forget_original_parent(current);
	iput(current->pwd);
	current->pwd = NULL;
	iput(current->root);
	current->root = NULL;
	iput(current->executable);
	current->executable = NULL;
	/* Release all of the old mmap stuff. */
	
	{
		struct vm_area_struct * mpnt, *mpnt1;
		mpnt = current->mmap;
		current->mmap = NULL;
		while (mpnt) {
			mpnt1 = mpnt->vm_next;
			if (mpnt->vm_ops && mpnt->vm_ops->close)
				mpnt->vm_ops->close(mpnt);
			kfree(mpnt);
			mpnt = mpnt1;
		}
	}

	if (current->ldt) {
		vfree(current->ldt);
		current->ldt = NULL;
		for (i=1 ; i<NR_TASKS ; i++) {
			if (task[i] == current) {
				set_ldt_desc(gdt+(i<<1)+FIRST_LDT_ENTRY, &default_ldt, 1);
				load_ldt(i);
			}
		}
	}

	current->state = TASK_ZOMBIE;
	current->exit_code = code;
	current->rss = 0;
	/* 
	 * Check to see if any process groups have become orphaned
	 * as a result of our exiting, and if they have any stopped
	 * jobs, send them a SIGUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 *
	 * Case i: Our father is in a different pgrp than we are
	 * and we were the only connection outside, so our pgrp
	 * is about to become orphaned.
 	 */
	if ((current->p_pptr->pgrp != current->pgrp) &&
	    (current->p_pptr->session == current->session) &&
	    is_orphaned_pgrp(current->pgrp) &&
	    has_stopped_jobs(current->pgrp)) {
		kill_pg(current->pgrp,SIGHUP,1);
		kill_pg(current->pgrp,SIGCONT,1);
	}
	/* Let father know we died */

    /* 通知父进程 */
	notify_parent(current);
	
	/*
	 * This loop does two things:
	 * 
  	 * A.  Make init inherit all the child processes
	 * B.  Check to see if any process groups have become orphaned
	 *	as a result of our exiting, and if they have any stopped
	 *	jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 */
	while ((p = current->p_cptr) != NULL) {
		current->p_cptr = p->p_osptr;
		p->p_ysptr = NULL;
		p->flags &= ~(PF_PTRACED|PF_TRACESYS);
		if (task[1] && task[1] != current)
			p->p_pptr = task[1];
		else
			p->p_pptr = task[0];
		p->p_osptr = p->p_pptr->p_cptr;
		p->p_osptr->p_ysptr = p;
		p->p_pptr->p_cptr = p;
		if (p->state == TASK_ZOMBIE)
			notify_parent(p);
		/*
		 * process group orphan check
		 * Case ii: Our child is in a different pgrp 
		 * than we are, and it was the only connection
		 * outside, so the child pgrp is now orphaned.
		 */
		if ((p->pgrp != current->pgrp) &&
		    (p->session == current->session) &&
		    is_orphaned_pgrp(p->pgrp) &&
		    has_stopped_jobs(p->pgrp)) {
			kill_pg(p->pgrp,SIGHUP,1);
			kill_pg(p->pgrp,SIGCONT,1);
		}
	}
	if (current->leader)
		disassociate_ctty(1);
	if (last_task_used_math == current)
		last_task_used_math = NULL;
#ifdef DEBUG_PROC_TREE
	audit_ptree();
#endif
	schedule();
/*
 * In order to get rid of the "volatile function does return" message
 * I did this little loop that confuses gcc to think do_exit really
 * is volatile. In fact it's schedule() that is volatile in some
 * circumstances: when current->state = ZOMBIE, schedule() never
 * returns.
 *
 * In fact the natural way to do all this is to have the label and the
 * goto right after each other, but I put the fake_volatile label at
 * the start of the function just in case something /really/ bad
 * happens, and the schedule returns. This way we can try again. I'm
 * not paranoid: it's just that everybody is out to get me.
 */
	goto fake_volatile;
}
Пример #23
0
static int read_chan(struct tty_struct *tty, struct file *file,
		     unsigned char *buf, unsigned int nr)
{
	struct wait_queue wait = { current, NULL };
	int c;
	unsigned char *b = buf;
	int minimum, time;
	int retval = 0;
	int size;

do_it_again:

	if (!tty->read_buf) {
		printk("n_tty_read_chan: called with read_buf == NULL?!?\n");
		return -EIO;
	}

	/* Job control check -- must be done at start and after
	   every sleep (POSIX.1 7.1.1.4). */
	/* NOTE: not yet done after every sleep pending a thorough
	   check of the logic of this change. -- jlc */
	/* don't stop on /dev/console */
	if (file->f_inode->i_rdev != CONSOLE_DEV &&
	    current->tty == tty) {
		if (tty->pgrp <= 0)
			printk("read_chan: tty->pgrp <= 0!\n");
		else if (current->pgrp != tty->pgrp) {
			if (is_ignored(SIGTTIN) ||
			    is_orphaned_pgrp(current->pgrp))
				return -EIO;
			kill_pg(current->pgrp, SIGTTIN, 1);
			return -ERESTARTSYS;
		}
	}

	if (L_ICANON(tty)) {
		minimum = time = 0;
		current->timeout = (unsigned long) -1;
	} else {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum) {
		  	current->timeout = (unsigned long) -1;
			if (time)
				tty->minimum_to_wake = 1;
			else if (!waitqueue_active(&tty->read_wait) ||
				 (tty->minimum_to_wake > minimum))
				tty->minimum_to_wake = minimum;
		} else {
			if (time) {
				current->timeout = time + jiffies;
				time = 0;
			} else
				current->timeout = 0;
			tty->minimum_to_wake = minimum = 1;
		}
	}

	add_wait_queue(&tty->read_wait, &wait);
	while (1) {
		/* First test for status change. */
		if (tty->packet && tty->link->ctrl_status) {
			if (b != buf)
				break;
			put_user(tty->link->ctrl_status, b++);
			tty->link->ctrl_status = 0;
			break;
		}
		/* This statement must be first before checking for input
		   so that any interrupt will set the state back to
		   TASK_RUNNING. */
		current->state = TASK_INTERRUPTIBLE;
		
		if (((minimum - (b - buf)) < tty->minimum_to_wake) &&
		    ((minimum - (b - buf)) >= 1))
			tty->minimum_to_wake = (minimum - (b - buf));
		
		if (!input_available_p(tty, 0)) {
			if (tty->flags & (1 << TTY_OTHER_CLOSED)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!current->timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (current->signal & ~current->blocked) {
				retval = -ERESTARTSYS;
				break;
			}
			schedule();
			continue;
		}
		current->state = TASK_RUNNING;

		/* Deal with packet mode. */
		if (tty->packet && b == buf) {
			put_user(TIOCPKT_DATA, b++);
			nr--;
		}

		if (L_ICANON(tty)) {
			while (1) {
				int eol;

				disable_bh(TQUEUE_BH);
				if (!tty->read_cnt) {
					enable_bh(TQUEUE_BH);
					break;
				}
				eol = clear_bit(tty->read_tail,
						&tty->read_flags);
				c = tty->read_buf[tty->read_tail];
				tty->read_tail = ((tty->read_tail+1) &
						  (N_TTY_BUF_SIZE-1));
				tty->read_cnt--;
				enable_bh(TQUEUE_BH);
				if (!eol) {
					put_user(c, b++);
					if (--nr)
						continue;
					break;
				}
				if (--tty->canon_data < 0) {
					tty->canon_data = 0;
				}
				if (c != __DISABLED_CHAR) {
					put_user(c, b++);
					nr--;
				}
				break;
			}
		} else {
			disable_bh(TQUEUE_BH);
			copy_from_read_buf(tty, &b, &nr);
			copy_from_read_buf(tty, &b, &nr);
			enable_bh(TQUEUE_BH);
		}

		/* If there is enough space in the read buffer now, let the
		   low-level driver know. */
		if (tty->driver.unthrottle &&
		    (tty->read_cnt <= TTY_THRESHOLD_UNTHROTTLE)
		    && clear_bit(TTY_THROTTLED, &tty->flags))
			tty->driver.unthrottle(tty);

		if (b - buf >= minimum || !nr)
			break;
		if (time)
			current->timeout = time + jiffies;
	}
	remove_wait_queue(&tty->read_wait, &wait);

	if (!waitqueue_active(&tty->read_wait))
		tty->minimum_to_wake = minimum;

	current->state = TASK_RUNNING;
	current->timeout = 0;
	size = b - buf;
	if (size && nr)
	        clear_bit(TTY_PUSH, &tty->flags);
        if (!size && clear_bit(TTY_PUSH, &tty->flags))
                goto do_it_again;
	if (!size && !retval)
	        clear_bit(TTY_PUSH, &tty->flags);
        return (size ? size : retval);
}
Пример #24
0
/* 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.
 */
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs * regs,
			 unsigned long orig_i0, int restart_syscall)
{
	unsigned long signr;
	siginfo_t info;
	struct k_sigaction *ka;
	
	if (!oldset)
		oldset = &current->blocked;

#ifdef CONFIG_SPARC32_COMPAT
	if (current->thread.flags & SPARC_FLAG_32BIT) {
		extern asmlinkage int do_signal32(sigset_t *, struct pt_regs *,
						  unsigned long, int);
		return do_signal32(oldset, regs, orig_i0, restart_syscall);
	}
#endif	
	for (;;) {
		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) {
			/* Do the syscall restart before we let the debugger
			 * look at the child registers.
			 */
			if (restart_syscall &&
			    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
			     regs->u_regs[UREG_I0] == ERESTARTSYS ||
			     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
				regs->u_regs[UREG_I0] = orig_i0;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				restart_syscall = 0;
			}

			current->exit_code = signr;
			current->state = TASK_STOPPED;
			notify_parent(current, SIGCHLD);
			schedule();
			if (!(signr = current->exit_code))
				continue;
			current->exit_code = 0;
			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;

                        /* sys_wait4() grabs the master kernel lock, so
                         * we need not do so, that sucker should be
                         * threaded and would not be that difficult to
                         * do anyways.
                         */
                        while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
                                ;
			continue;
		}
		if (ka->sa.sa_handler == SIG_DFL) {
			unsigned long exit_code = signr;
			
			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;

			case SIGSTOP:
				if (current->ptrace & PT_PTRACED)
					continue;
				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;
#ifdef DEBUG_SIGNALS
				/* Very useful to debug the dynamic linker */
				printk ("Sig %d going...\n", (int)signr);
				show_regs (regs);
#ifdef DEBUG_SIGNALS_TRACE
				{
					struct reg_window *rw = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
					unsigned long ins[8];
                                                
					while (rw &&
					       !(((unsigned long) rw) & 0x3)) {
					        copy_from_user(ins, &rw->ins[0], sizeof(ins));
						printk("Caller[%016lx](%016lx,%016lx,%016lx,%016lx,%016lx,%016lx)\n", ins[7], ins[0], ins[1], ins[2], ins[3], ins[4], ins[5]);
						rw = (struct reg_window *)(unsigned long)(ins[6] + STACK_BIAS);
					}
				}
#endif			
#ifdef DEBUG_SIGNALS_MAPS	
				printk("Maps:\n");
				read_maps();
#endif
#endif
				/* fall through */
			default:
				sig_exit(signr, exit_code, &info);
				/* NOT REACHED */
			}
		}
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka->sa);
		handle_signal(signr, ka, &info, oldset, regs);
		return 1;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
	return 0;
}
Пример #25
0
int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
	siginfo_t info;
	struct k_sigaction *ka;
	unsigned long frame, newsp;

	/*
	 * If the current thread is 32 bit - invoke the
	 * 32 bit signal handling code
	 */
	if (current->thread.flags & PPC_FLAG_32BIT)
		return do_signal32(oldset, regs);

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

	newsp = frame = 0;

	for (;;) {
		unsigned long signr;

                PPCDBG(PPCDBG_SIGNAL, "do_signal - (pre) dequeueing signal - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
		spin_lock_irq(&current->sigmask_lock);
		signr = dequeue_signal(&current->blocked, &info);
		spin_unlock_irq(&current->sigmask_lock);
                PPCDBG(PPCDBG_SIGNAL, "do_signal - (aft) dequeueing signal - signal=%lx - pid=%ld current=%lx comm=%s \n", signr, current->pid, current, current->comm);

		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];

  
                PPCDBG(PPCDBG_SIGNAL, "do_signal - ka=%p, action handler=%lx \n", ka, ka->sa.sa_handler);

		if (ka->sa.sa_handler == SIG_IGN) {
                        PPCDBG(PPCDBG_SIGNAL, "do_signal - into SIG_IGN logic \n");
			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;
                        PPCDBG(PPCDBG_SIGNAL, "do_signal - into SIG_DFL logic \n");

			/* 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: {
				struct signal_struct *sig;
				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, 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.  */
  
                PPCDBG(PPCDBG_SIGNAL, "do_signal - GOING TO RUN SIGNAL HANDLER - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
		handle_signal(signr, ka, &info, oldset, regs, &newsp, frame);
                PPCDBG(PPCDBG_SIGNAL, "do_signal - after running signal handler - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
                break;
	}

	if (regs->trap == 0x0C00 /* System Call! */ &&
	    ((int)regs->result == -ERESTARTNOHAND ||
	     (int)regs->result == -ERESTARTSYS ||
	     (int)regs->result == -ERESTARTNOINTR)) {
                PPCDBG(PPCDBG_SIGNAL, "do_signal - going to back up & retry system call \n");
		regs->gpr[3] = regs->orig_gpr3;
		regs->nip -= 4;		/* Back up & retry system call */
		regs->result = 0;
	}

	if (newsp == frame)
          {
             PPCDBG(PPCDBG_SIGNAL, "do_signal - returning w/ no signal delivered \n");
             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);
        PPCDBG(PPCDBG_SIGNAL, "do_signal - returning a signal was delivered \n");
	return 1;
}
Пример #26
0
/* 
 * Send signals to all our closest relatives so that they know
 * to properly mourn us..
 */
static void exit_notify(void)
{
	struct task_struct * p;

	forget_original_parent(current);
	/* 
	 * Check to see if any process groups have become orphaned
	 * as a result of our exiting, and if they have any stopped
	 * jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 *
	 * Case i: Our father is in a different pgrp than we are
	 * and we were the only connection outside, so our pgrp
	 * is about to become orphaned.
	 */
	if ((current->p_pptr->pgrp != current->pgrp) &&
	    (current->p_pptr->session == current->session) &&
	    will_become_orphaned_pgrp(current->pgrp, current) &&
	    has_stopped_jobs(current->pgrp)) {
		kill_pg(current->pgrp,SIGHUP,1);
		kill_pg(current->pgrp,SIGCONT,1);
	}
	/* Let father know we died */
	notify_parent(current);
	
	/*
	 * This loop does two things:
	 * 
  	 * A.  Make init inherit all the child processes
	 * B.  Check to see if any process groups have become orphaned
	 *	as a result of our exiting, and if they have any stopped
	 *	jobs, send them a SIGHUP and then a SIGCONT.  (POSIX 3.2.2.2)
	 */
	while ((p = current->p_cptr) != NULL) {
		current->p_cptr = p->p_osptr;
		p->p_ysptr = NULL;
		p->flags &= ~(PF_PTRACED|PF_TRACESYS);
		if (task[smp_num_cpus] && task[smp_num_cpus] != current) /* init */
			p->p_pptr = task[smp_num_cpus];
		else
			p->p_pptr = task[0];
		p->p_osptr = p->p_pptr->p_cptr;
		p->p_osptr->p_ysptr = p;
		p->p_pptr->p_cptr = p;
		if (p->state == TASK_ZOMBIE)
			notify_parent(p);
		/*
		 * process group orphan check
		 * Case ii: Our child is in a different pgrp 
		 * than we are, and it was the only connection
		 * outside, so the child pgrp is now orphaned.
		 */
		if ((p->pgrp != current->pgrp) &&
		    (p->session == current->session) &&
		    is_orphaned_pgrp(p->pgrp) &&
		    has_stopped_jobs(p->pgrp)) {
			kill_pg(p->pgrp,SIGHUP,1);
			kill_pg(p->pgrp,SIGCONT,1);
		}
	}
	if (current->leader)
		disassociate_ctty(1);
}